This invention relates to a newly discovered form of AC signal processing distortion and means for reducing this distortion. In the prior art, many sources of signal processing distortions have been identified, quantified and reduced. Each of the many components which make up AC signal processing systems contribute some known form of distortion. Active devices such as transistors or FET's have non-linear transfer characteristics which cause amplitude related distortions such as harmonic and intermodulation distortion. Passive devices, such as resistors and capacitors, introduce phase or time related distortions as a result of both structure and the materials used in construction of such components.
This invention addresses hitherto, unrecognized electromagnetic field effects which we have discovered to be a significant remaining cause of signal degradation in all AC signal processing systems. We have developed techniques for reducing this form of signal degradation in individual components, as well as that resulting from complex multi-stage AC signal processing systems. As a convenience we have named this newly identified signal degradation as "State" distortion. This type of signal distortion is correctable by the unique multi-junction conductive structures, of the subject invention. This form of State distortion, occurs in active and passive components, wires, printed circuit assemblies, and in most electromagnetic transducers. We also believe that the corrective devices and practices of this invention relate to eddy current effects in conductive materials.
Several technical papers are worth noting as background for this patent. A Model of Loudspeaker Driver Impedance Incorporating Eddy Currents in the Pole Structure, by John Vanderkooy, March 1989 Vol.37 No. 3, pp 119-128, Jour Audio Eng. Soc., analyzes the dispersive related energy storage and "semi-inductive" phase effects of eddy currents in permeable conductive materials. In Stereophile magazine, October 1995, pp 63 to 69 a paper by Malcolm O. Hawksford of The University of Essex examines electrical signal propagation in non permeable conductors from the point of view of audio transmission line performance. This paper also discuses the effects of highly dispersive eddy currents as a contributing factor to time delayed energy storage in conductors. In The Philips Technical Revue, Vol. 32 pp 226-231, No. 6,7&8, 1971, V. Belevitch mathematically analyzes eddy current distribution in ribbon conductors.
We have observed that in sound reproduction or reinforcement the effects of State distortions are perceived as a loss of stereo image information, alterations in the harmonic structures of signals produced by musical instruments, and inaccuracies in the dynamic characterisics, especially noticeable in reproduction of the human voice. The well known harshness and truncation of ambient decay information of digital signal processing and recording, appears to be at least partially a form of State distortion, whose objectionable effects some forms of the subject invention appear to correct.
In video or other image electrical signal processing. State distortions result in compression of color and gray scale, reduced picture detail and exaggeration of color and contrast. These effects combine to degrade the perception of front to back object depth so that a typical video picture is both flatter in perspective and less natural in color. The improvements of the subject invention result in video images which resemble the best printed color reproductions of works of art.
As a practical matter, it is virtually impossible to correct each of the hundreds if not thousands of the random, such State caused distortions that must occur in virtually every signal processing system. We have found that the State distortion correction devices of this invention have a unique ability to reduce such distortions after they have been generated, in a degree unachievable even with complex digital error correcting circuits. We know of no other methodology of the prior art which addresses and reduces this form of distortion to the degree, or in such a practical and cost effective manner, as that achieved by the subject invention.